Table 5.

Trend analysis of plaque-free, periodontal health, and deep pockets in adults aged 25–54 from the Dutch National Oral Health Survey 1995–2013

Adjusted OR (95% CI)	Plaque-free	Periodontal health	Deep pockets
Total population
Survey year
1995	1 [reference]	1 [reference]	1 [reference]
2002	0.752 (0.539 to 1.048)	0.893 (0.733 to 1.090)	1.155 (0.792 to 1.686)
2007	2.073 (1.546 to 2.779)	1.289 (1.043 to 1.593)	1.102 (0.728 to 1.669)
2013	3.158 (2.372 to 4.206)	1.542 (1.242 to 1.913)	0.883 (0.562 to 1.388)
P for temporal trend a	.000	.000	.652
Low-SES population
Survey year
1995	1 [reference]	1 [reference]	1 [reference]
2002	0.754 (0.506 to 1.123)	.817 (0.645 to 1.036)	1.071 (0.703 to 1.631)
2007	1.730 (1.136 to 2.634)	1.248 (0.935 to 1.665)	1.038 (0.626 to 1.722)
2013	2.915 (1.914 to 4.438)	1.259 (0.922 to 1.718)	0.882 (0.502 to 1.548)
P for temporal trend a	.000	.083	.893
High-SES population
Survey year
1995	1 [reference]	1 [reference]	1 [reference]
2002	0.669 (0.353 to 1.266)	1.075 (0.741 to 1.559)	1.633 (0.690 to 3.865)
2007	2.525 (1.644 to 3.879)	1.359 (0.988 to 1.869)	1.410 (0.646 to 3.080)
2013	3.501 (2.316 to 5.292)	1.793 (1.312 to 2.449)	1.061 (0.470 to 2.397)
P for temporal trend a	.000	.000	.787
P for interaction b	.198	.490	.678

All logistic regression models were adjusted for including age, gender, ethnicity, SES, time since the last dental visit, number of teeth present, and oral hygiene behaviors (toothbrushing frequency, floss usage, and toothpick usage). Low-SES was regarded as reference

^aAll P for trends were calculated using survey year as a continuous variable

^bThe interaction term indicated survey year × SES

Bold indicates P value < .05